This invention relates to an oral composition which can prevent periodontal disease through suppression of the intraoral colonization of Bacteroides gingivalis which is one of the causative bacteria of periodontal diseases.
There are many people having periodontal disease such as gingivitis and periodontitis. The rate of such disease in adults is especially on the increase. Prevention of periodontal diseases will be an important problem in the future circumstance because of an ever increasing number of aged persons.
Periodontal disease is primarily caused by bacteria existing in accumulated plaque in periodontal pockets. A healthy periodontal pocket is usually composed of an overwhelming amount of gram positive bacteria, while the amount of gram negative bacteria increases with the progress of the periodontal disease. Bacteroides gingivalis, Fusobacterium nucleatum, Eikenella corrodens, Actionabacillus actinomycetemcomitans and so forth are primarily listed as such gram negative bacteria. In the focal regions of adult patients with severe periodontal disease, gram negative bacteria are detected in most cases among which Bacteroides gingivalis is separated in a specially high frequency. In many of these cases, the titer of anti-Bacteroides gingivalis antibody in the serum of the patient also increases. In addition, it has been demonstrated that the inoculation of an animal with Bacteroides gingivalis aggravates periodontal inflammation. These results indicate that Bacteroides gingivalis plays an important role in the development of periodontal diseases.
Bacteroides gingivalis adheres to periodontal mucosa by means of its pili and capsule existing on the surface of its bacterial body, thereby proliferating and badly influencing the periodontal region. For the prevention of periodontal diseases, the inhibition of the colonization or suppression of the proliferation of Bacteroides gingivalis in the mouth is effective and bactericides are mainly used now for this purpose. In some more specific methods, the inhibition of the colonization of Bacteroides gingivalis in the mouth is attempted by using a vaccine. However, since the bacterial body is used as an active vaccine which is directly injected into the living human body in all of these methods, they have problems in terms of both effect and toxicity.